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Issue Title: Special Issue: Science Results from the Canadian International Polar Year 2007-2008 Tundra and taiga ecosystems comprise nearly 40 % of the terrestrial landscapes of Canada. These permafrost ecosystems have supported humans for more than 4500 years, and are currently home to ca. 115,000 people, the majority of whom are First Nations, Inuit and Métis. The responses of these ecosystems to the regional warming over the past 30-50 years were the focus of four Canadian IPY projects. Northern residents and researchers reported changes in climate and weather patterns and noted shifts in vegetation and other environmental variables. In forest-tundra areas tree growth and reproductive effort correlated with...
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This dataset represents presence of Jack Pine (Pinus banksiana) in Minnesota (USA) at year 50 (2045) from a single model run of LANDIS-II. The simulation assumed Intergovernmental Panel on Climate Change (IPCC) B2 emissions (moderate) and used the Hadley 3 global circulation model. Restoration harvest rates and intensities were simulated.
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This dataset represents presence of Sugar Maple (Acer saccharum) in Minnesota (USA) at year 0 (2145) from a single model run of LANDIS-II. The simulation assumed Intergovernmental Panel on Climate Change (IPCC) B2 emissions (moderate) and used the Hadley 3 global circulation model. Contemporary harvest rates and intensities were simulated.
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Detailed observations of stream, soil, and groundwater chemistry were used to determine the role of fire, permafrost and snowmelt processes on the fluxes of carbon, nitrogen and major solutes from interior Alaskan catchments. We examined an experimentally burned watershed and two reference watersheds that differ in permafrost coverage (high, 53%; medium-burn, 18%; and low, 4%) during the FROSTFIRE prescribed burn in July 1999. The fire elevated stream nitrate concentrations for a short period during the first post-fire storm, but nitrate declined thereafter, suggesting that less severe fires that leave an intact riparian zone may have only a short-term effect on stream chemistry. Nevertheless, we found fundamental...
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This EnviroAtlas web service supports research and online mapping activities related to EnviroAtlas (https://www.epa.gov/enviroatlas). The Food, Fuel, and Materials category in this web service includes layers illustrating the ecosystems and natural resources that provide or support the production of food, fuel, or other materials, the need or demand for these items, the impacts associated with their presence and accessibility, and factors that place stress on the natural environment's capability to provide these benefits. EnviroAtlas allows the user to interact with a web-based, easy-to-use, mapping application to view and analyze multiple ecosystem services for the conterminous United States. Additional descriptive...
Types: Citation; Tags: Society, Environmental Justice, Endangered, Supply of Ecosystem Services, Response, All tags...
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The evolution of permafrost in cold regions is inextricably connected to hydrogeologic processes, climate, and ecosystems. Permafrost thawing has been linked to changes in wetland and lake areas, alteration of the groundwater contribution to streamflow, carbon release, and increased fire frequency. But detailed knowledge about the dynamic state of permafrost in relation to surface and groundwater systems remains an enigma. Here, we present the results of a pioneering 1,800 line-kilometer airborne electromagnetic survey that shows sediments deposited over the past 4 million years and the configuration of permafrost to depths of 100 meters in the Yukon Flats area near Fort Yukon, Alaska. The Yukon Flats is near the...
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This thesis is an investigation of the biophysical controls on the three modes of methane (CH4 ) release from a boreal peatland: diffusion, plant-mediated transport and ebullition. My objectives were to (1) quantify the total CH4 flux of a permafrost thaw-affected peatland, (2) establish the relative importance of the three modes of CH4 release in these systems, and (3) identify key biotic and abiotic controls on individual transport mechanisms. Results showed that ebullition and plant-mediated transport were the dominant pathways for CH4 release and that traditional approaches for measuring total CH4 flux from peatland soils underestimated total efflux by not capturing ebullition. Further, results from a laboratory...
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This dataset contains csv files in support of the conclusions published in "Water use demand in Mediterranean California under multiple scenarios of developed and agricultural land use " in the journal PLOS One. We used the USGS's LUCAS model to examine a broad suite of spatially explicit future land use scenarios and their associated county-level water use demand, including the historical (1992-2011) and projected periods (2012-2062) across 40 Monte Carlo simulations.We examined a range of potential water demand futures sampled from a 20-year record of historical (1992-2012) data to develop a suite of potential future land change scenarios from 2012-2062. These scenario simulations include a 1) business-as-usual...
Snow covered area (SCA) observations from the Landsat Enhanced Thematic Mapper (ETM+) were used in combination with a distributed snowmelt model to estimate snow water equivalent (SWE) in the headwaters of the Rio Grande basin (3,419 km2) - a spatial scale that is an order of magnitude greater than previous reconstruction model applications. In this reconstruction approach, modeled snowmelt over each pixel is integrated over the time of ETM+ observed snow cover to estimate SWE. Considerable differences in the magnitude of SWE were simulated during the study. Basin-wide mean SWE was 2�6 times greater in April 2001 versus 2002. Despite these climatological differences, the model adequately recovered SWE at intensive...
A severe sustained drought in the Colorado River Basin would cause economic damages throughout the Basin. An integrated hydrologic-economic-institutional model introduced here shows that consumptive water users in headwaters states are particularly vulnerable to very large shortfalls and hence large damages because their rights are effectively junior to downstream users. Chronic shortfalls to consumptive users relying on diversions in excess of rights under the Colorado River Compact are also possible. Nonconsumptive water uses (for hydropower and recreation) are severely affected during the worst drought years as instream flows are reduced and reservoirs are depleted. Damages to these uses exceeds those to consumptive...
This dataset consists of the current distribution (2000s) of mangrove forests in the southeastern U.S. This dataset was created from the current best available mangrove data on a state specific basis. Florida mangrove data was extracted from Florida Landuse Land Cover Classification System (FLUCCS). For Louisiana, we used observations of mangrove stands from aerial surveys by Michot et al. (2010). Mangrove presence in Texas came from maps produced by Sherrod & McMillan (1981) and the NOAA Benthic Habitat Atlas of Coastal Texas (Finkbeiner et al. 2009). Please note that this map depicts the distribution of mangrove forests and not mangrove individuals. More detailed information on this dataset is available in Osland...
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Pogo Mine Project: An Introduction The Project: The proposed Pogo Gold Mine would be located about 38 miles northeast of Delta Junction, Alaska, near the Goodpaster River (see figure 1). Teck-Pogo, Inc., the "applicant," plans to develop the mine on state-owned land. It would be an underground mine with a surface mill producing up to 500,000 ounces of gold each year. The applicant hopes to begin construction in 2002, and proposes to operate the mine 24 hours a day, 365 days a year, for about 12 years. This predicted mine-life is based on existing information; on-going exploration could increase the life of the mine. The project would employ up to 385 employees. Workers would be housed on site. An airstrip would...
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This paper examines changes in climate with respect to permafrost and engineering design in Arctic regions. Current understanding of climate changes, predictive modeling, and climate data were studied. Inconsistencies and differences were noted, discussed, and evaluated using comparisons of the resulting climate data and graphs. A graphical analysis was done to compare different methods of data analysis and different visual interpretations of historical climate trends. The graphical analyses in this paper should be used as a guide for determining the accuracy of thermal design parameters applied to current project designs. The methodology used to evaluate raw data can greatly affect the output values used in design....
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Permanent electrode arrays were set up at ten monitoring sites from Whitehorse, Yukon, to Fort St. John, British Columbia, in order to gain a clearer perspective of the effectiveness of electrical resistivity tomography (ERT) monitoring over an annual cycle of freezing and thawing. This research forms part of a longer-term project that is attempting to use ERT to examine changes in permafrost resulting from climate change. Inter-site and intra-site variability were examined by installing and maintaining data-loggers to monitor active layer and shallow permafrost temperatures, air temperatures, and snow depths at each site from August 2010-August 2011. Additional site information was collected on each ERT survey...
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We investigated spatial variability in the community structure of stream macroinvertebrates at six reaches within Caribou-Poker Creeks Research Watershed in the Alaskan taiga forest. Stream reaches differed most notably in river continuum position (stream orders 1–4) and influence of permafrost. Permafrost may underly much of an entire watershed or may be only locally present in valley bottoms. Permafrost distribution influences hydrology, water temperature, and riparian vegetation. We sampled benthic macroinvertebrates six times during the ice-free season between June 1995 and June 1996. Mean invertebrate abundance (range: 1160–14494 individuals/ m2) was significantly different among sites, the lower values occurring...
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Understanding the role of permafrost in controlling groundwater flow paths and fluxes is central in studies aimed at assessing potential climate change impacts on vegetation, species habitat, biogeochemical cycling, and biodiversity. Recent field studies in interior Alaska show evidence of hydrologic changes hypothesized to result from permafrost degradation. This study assesses the hydrologic control exerted by permafrost, elucidates modes of regional groundwater flow for various spatial permafrost patterns, and evaluates potential hydrologic consequences of permafrost degradation. The Yukon Flats Basin (YFB), a large (118,340 km super(2)) subbasin within the Yukon River Basin, provides the basis for this investigation....
map background search result map search result map Minnesota (USA) Climate Change Project: Jack Pine at Year 50 (2045), assuming emissions scenario B2, Hadley3 GCM, restoration harvest rates and intensity Minnesota (USA) Climate Change Project: Sugar Maple at Year 150 (2145), assuming emissions scenario B2, Hadley3 GCM, contemporary harvest rates and intensity EnviroAtlas - Food, Fuel, and Materials Metrics for Conterminous United States Effects of observed and experimental climate change on terrestrial ecosystems in northern Canada: results from the Canadian IPY program Airborne electromagnetic imaging of discontinuous permafrost The effect of fire and permafrost interactions on soil carbon accumulation in an upland black spruce ecosystem of interior Alaska: implications for post-thaw carbon loss Influence of permafrost distribution on groundwater flow in the context of climate-driven permafrost thaw: Example from Yukon Flats Basin, Alaska, United States Physical and ecological controls on methane release from a boreal peatland in interior Alaska Exploring the sensitivity of soil carbon dynamics to climate change, fire disturbance and permafrost thaw in a black spruce ecosystem Seasonal cycling in electrical resistivities at ten thin permafrost sites, southern Yukon and northern British Columbia “The Worst Thing We Had To Contend With”: Permafrost and Construction of the Alcan Highway Export of carbon, nitrogen and major solutes from a boreal forest watershed: The influence of fire and permafrost Landscape patterns and stream reaches in the Alaskan taiga forest: potential roles of permafrost in differentiating macroinvertebrate communities POGO Gold Mine EIS/NEPA Project Progress in space-borne studies of permafrost for climate science: Towards a multi-ECV approach Mediterranean California’s water use future based on scenarios of land use change 1992-2062 - Tabular Data POGO Gold Mine EIS/NEPA Project Landscape patterns and stream reaches in the Alaskan taiga forest: potential roles of permafrost in differentiating macroinvertebrate communities Physical and ecological controls on methane release from a boreal peatland in interior Alaska Export of carbon, nitrogen and major solutes from a boreal forest watershed: The influence of fire and permafrost Exploring the sensitivity of soil carbon dynamics to climate change, fire disturbance and permafrost thaw in a black spruce ecosystem Minnesota (USA) Climate Change Project: Sugar Maple at Year 150 (2145), assuming emissions scenario B2, Hadley3 GCM, contemporary harvest rates and intensity Minnesota (USA) Climate Change Project: Jack Pine at Year 50 (2045), assuming emissions scenario B2, Hadley3 GCM, restoration harvest rates and intensity Airborne electromagnetic imaging of discontinuous permafrost Influence of permafrost distribution on groundwater flow in the context of climate-driven permafrost thaw: Example from Yukon Flats Basin, Alaska, United States Seasonal cycling in electrical resistivities at ten thin permafrost sites, southern Yukon and northern British Columbia “The Worst Thing We Had To Contend With”: Permafrost and Construction of the Alcan Highway The effect of fire and permafrost interactions on soil carbon accumulation in an upland black spruce ecosystem of interior Alaska: implications for post-thaw carbon loss Mediterranean California’s water use future based on scenarios of land use change 1992-2062 - Tabular Data Effects of observed and experimental climate change on terrestrial ecosystems in northern Canada: results from the Canadian IPY program Progress in space-borne studies of permafrost for climate science: Towards a multi-ECV approach EnviroAtlas - Food, Fuel, and Materials Metrics for Conterminous United States